鼠李糖乳杆菌对免疫检查点抑制剂相关小鼠结肠炎的保护作用及其机制  

Protective effect and mechanism of Lactobacillus rhamnosus on immune checkpoint inhibitors related colitis in mice

作　　者：谭蓓[1] 唐颢[2] 徐燕[3] 陈闽江[3] 王孟昭[3] 钱家鸣[1] Tan Bei;Tang Hao;Xu Yan;Chen Minjiang;Wang Mengzhao;Qian Jiaming(Department of Gastroenterology,Peking Union Medical College Hospital,Peking Union Medical College,Chinese Academy of Medical Science,Beijing 100730,China;Department of Internal Medicine,Peking Union Medical College Hospital,Peking Union Medical College,Chinese Academy of Medical Science,Beijing 100730,China;Department of Respiratory and Critical Care Medicine,Peking Union Medical College Hospital,Peking Union Medical College,Chinese Academy of Medical Science,Beijing 100730,China)

机构地区：[1]中国医学科学院,北京协和医学院,北京协和医院消化内科,北京100730 [2]中国医学科学院,北京协和医学院,北京协和医院内科,北京100730 [3]中国医学科学院,北京协和医学院,北京协和医院呼吸与危重症医学科,北京100730

出　　处：《中华医学杂志》2020年第42期3332-3337,共6页National Medical Journal of China

基　　金：北京市自然科学基金(7192172)。

摘　　要：目的建立小鼠免疫治疗相关(irAE)结肠炎模型,探讨鼠李糖乳杆菌(LGG)对irAE结肠炎的保护作用和相关机制。方法C57BL/6小鼠分为葡聚糖硫酸钠(DSS)组3只、DSS+抗程序性死亡受体1(PD-1)组4只,DSS+抗PD-1+抗细胞毒性T淋巴细胞相关蛋白4(CTLA-4)组4只、DSS+抗PD-1+抗CTLA-4+LGG组4只,分别给予相应药物和菌群干预。通过体重下降、疾病活动指数(DAI)、结肠长度、结肠组织病理评分,实时荧光定量-聚合酶链式反应(qRT-PCR)检测结肠组织炎性细胞因子,免疫组化染色CD4^+、CD8^+和FoxP3^+调节T细胞。结果与DSS组比较,DSS+抗PD-1+抗CTLA-4组小鼠第9天体重[(87.40±1.79)%比(94.57±0.53)%]和结肠长度[(5.33±0.27)cm比(6.63±0.12)cm]较低(P<0.05),DAI评分(2.66±0.24比0.89±0.48)、结肠组织病理评分(12.50±1.04比5.67±0.33)、肿瘤坏死因子α(TNF-α)(6.73±1.68比0.91±0.40)较高(P<0.05);CD8^+T细胞(156.80±8.84比89.00±6.66)和FoxP3^+调节性T细胞(Treg)(103.80±2.66比48.33±3.18)较多(P<0.05)。与DSS+抗PD-1+抗CTLA-4组比较,DSS+抗PD-1+抗CTLA-4+LGG组小鼠DAI评分(1.83±0.17比2.66±0.24)、结肠组织病理评分(8.75±0.63比12.50±1.04)、炎性因子TNF-α(1.32±0.18比6.73±1.68)均较低(P<0.05);CD8^+T细胞较少(97.75±3.75比156.80±8.84,P<0.01),FoxP3^+Treg细胞较多(126.00±8.33比103.80±2.66,P=0.046)。结论DSS联合抗PD-1和抗CTLA-4成功构建小鼠irAE结肠炎模型,补充LGG通过调节Treg细胞减轻irAE结肠炎。Objective Modeling the immune-related adverse events(irAE)colitis in mice,and explore the protective effect and related mechanism of Lactobacillus rhamnosus GG(LGG)on irAE colitis.Methods C57BL/6 mice were divided into dextran sodium sulfate(DSS)group(n=3),DSS+anti-programmed death receptor 1(PD-1)group(n=4),DSS+anti-PD-1+anti-cytotoxic T lymphocyte associated protein 4(CTLA-4)Group(n=4),DSS+anti-PD-1+anti-CTLA-4+LGG group(n=4),all were given corresponding drugs and probiotics intervention.The severity of colitis were assessed by weight loss,disease activity index(DAI),colon length,colon histopathological score.The inflammatory cytokines and T cell immunity of CD4^+,CD8^+,FoxP3^+regulatory T cells(Treg),were detected by real-time quantitative reverse transcription-polymerase chain reaction(qRT-PCR)and immunohistochemical staining respectively.Results Compared to DSS group,the Day 9 weight[(87.40±1.79)%vs(94.57±0.53)%,P<0.05],colon length[(5.33±0.27)cm vs(6.63±0.12)cm,P<0.05]were lower,and DAI score(2.66±0.24 vs 0.89±0.48),colon histopathological score(12.50±1.04 vs 5.67±0.33),tumor necrosis factor-α(TNF-α)(6.73±1.68 vs 0.91±0.40)(P<0.05),as well CD8^+T cells(156.80±8.84 vs 89.00±6.66)and FoxP3^+Treg cells(103.80±2.66 vs 48.33±3.18)(P<0.05)were higher in DSS+anti-PD-1+anti-CTLA-4 group.Compared to DSS+anti-PD-1+anti-CTLA-4 group,the DAI score(1.83±0.17 vs 2.66±0.24),colonic histopathology score(8.75±0.63 vs 12.50±1.04),TNF-αlevel(1.32±0.18 vs 6.73±1.68)(P<0.05)were lower;and CD8^+T cells(97.75±3.75 vs 156.80±8.84,P<0.01)level was lower with higher FoxP3^+Treg cells(126.00±8.33 vs 103.80±2.66,P=0.046)in DSS+anti-PD-1+anti-CTLA-4+LGG group.Conclusion DSS combined with anti-PD-1 and anti-CTLA-4 can successfully modeling the irAE colitis in mice,LGG can reduce irAE colitis severity by regulating Treg cells.

关 键 词：结肠炎 免疫治疗相关不良反应 鼠李糖乳杆菌 T细胞免疫 

分 类 号：R574.62[医药卫生—消化系统]